Tutorials

Why I choose Redpine RSI9116

Recently. I'm studying in low power consumption module for WI-FI application, I using Texas Instruments CC3220 MCU develop my project at the beginning. CC3220 have great performed at power consumption and easy using platform(have a lot Free RTOS resource ), have another m0 MCU inside the SoC which can building application code. But it can't change main clock source(just fix at 80MHz), It will be okay with some project, but it will be deadly problem with project using battery .At the same time I found Redpine RSI9116(maybe recent Silicon labs acquisition it),Have better WI-FI power consumption than CC3220, And can connect it just thought AT command. It totally fitty my demand ,almost the gospel for me

Why write library by myself

Redpine have abundant example coed with WIFI host, but most of that are is for sapis communicate, and Redpine library is coding base on Free RTOS ,In my application, using bare metal environment is enough(less code size and better power consumption ).so I decide write a library by myself

Implement Flow Chart

This is the flow chart implement RS9116 AT Command BSP Using STM32 Nucleo board

1.RS9116 EVM Firmware update

Need update RS9116 module FW to Version 2.0 ( Different FW version will effect AT Command parameter) , Can just reference silicon lab opensource document below

AN1290: RS9116W Firmware Update Application Note

2.Load AWS Certificate using python script

For security ,Burn certificate in module before using it is better way than sent by host MCU

Silicon provide simple Python 2.7 script to upload AWS certificate to RS9116 module. but little complex.

so my project also provide python script at one click

3.STM board setting and Import library

(1).Create STM project

In my library have using DMA UART peripheral .need config first( also can just modify form my example , just slight change in GPIO port and DMA channel )

Note 1: Can't using DMA channel 3 used for UART data reception

(2).Import bsp_rf/bsp_uart library to STM project

(3).Config MQTT setting in bsp_rf.c

const char * SSID="WIFI SSID";
const char * SSID_password="Yours WIFI password";
const char * AWS_endpoint="--Yours AWS endpoint----.iot.----.amazonaws.com";
const char * MQTT_Server_Port="8883";
const char * Device_ID="Yours Device ID";
const char * MQTT_username="username";
const char * MQTT_password="password";
const char * MQTT_client_port="5503";
const char * MQTT_keep_alive_interval="80";
const char * MQTT_En_clean_session="1";
const char * MQTT_En_keep_alive_interval="1";
const char * MQTT_Sub_Topic="topic/Sub";
const char * MQTT_Pub_Topic="topic/Pub";
const char * MQTT_Sub_Objet="{\"msg\":";

(4).Running Testing code in main c

int main(void)
{

  HAL_Init();  
  SystemClock_Config(); 
  MX_GPIO_Init();  
  BSP_UART_Init();
  BSP_RF_RS9116_Init();
  BSP_RF_RS9116_WIFI_Connect();
  BSP_RF_RS9116_MQTT_Connect();
  /*MQTT Subscribe */
  BSP_RF_RS9116_MQTT_Subscribe((char *)MQTT_Sub_Topic);
   /*MQTT Publish */
  static char mqtt_pub_data[100];
  BSP_RF_RS9116_JSON_Encode(mqtt_pub_data,"Object1","Data1","Object2","On");
  BSP_RF_RS9116_MQTT_Publish((char *)MQTT_Pub_Topic,mqtt_pub_data);
  BSP_RF_RS9116_JSON_Encode(mqtt_pub_data,"Object2","Data1","state","Off");
  BSP_RF_RS9116_MQTT_Publish((char *)MQTT_Pub_Topic,mqtt_pub_data);
  while (1)
  {
	if(BSP_RF_MQTT_CMD_Pop()!=CMD_EMPTY)
	{
		BSP_RF_RS9116_MQTT_DisConnect();
	}
  }
}

4.Test

Unfortunately, In RS9116 EVM Board don't have TX/RX pinout directly(can't bypass form USB virtual comport driver at EVM ), I try connect GPIO_8 (RSI9116 TX),GPIO_9 (RSI9116 RX) by jumper . and USB port just plug in(J23) Power port (Not (J21)UART port ). But still have some bug and unstable(If have better solution please tell me)

In the end I wrote a python script, just simple exchange data between two virtual comport ,and monitor by CMD( you also can find this script form my git project),Block diagram is below

Using this python script, In Hardware setting is more simple just connect STM and RSI 9116 EVM(J21) in USB port .After Execute python script , choose right virtual comport , it will start working

Sample Testing in YouTube :

https://www.youtube.com/watch?v=L9ByurI4_Xg&feature=youtu.be

Why Opensource

I'm working at a Start-up Company in Taiwan ,I'm very new at HW and FW design, but need lead whole project(actually only me in the team at beginning), you can image that how hopeless and helpless at that period.

Luckily, I met my mentor Zhih-Tai, Liu last year (He is a freelancer and also have a Electro-Hedgehog in Taiwan Tasker ), He teach me a lot at HW designed and FW coding concept. We often discussing some designed excitedly

so I decide pass this passion to who struggling in same situation but no have abundant resource

In the end , thank my partner chase hu, you are so support no only in HW and ME but also in design ideas